Perhaps if the Duke and Duchess had done something worthwhile with the latter part of their lives there might be more sympathy for them, flawed though they were. Edward was still admired by a certain section of the British population in a nostalgic sort of way. He could have done so much for wounded and maimed ex servicemen after the war, even if he'd remained in France and done his bit for French servicemen, allies of the British.
If he had immersed himself in that, if she had thrown herself into relief work for the poor of Paris, international refugees of which there were many after World War 2, care of the sick, something, anything heartfelt, then they would at least have shown they were capable of thinking of others beyond their immediate circle.
Instead, there were regular trips on transatlantic liners, long stays at friends' homes in Italy, the US, Portugal, even England. She decorated their two houses, they both entertained, they were great partygoers, etc etc., a completely hedonistic lifestyle that lasted until Edward's final illness. The Duchess was a totally self absorbed individual, she was the centre of his world in a very obsessive way, and that says it all really. No thought for anyone else but themselves ever.